1 Jamie: Okay. With our show's budget we can't afford enough dynamite to blow all of the water out of Loch Ness.
2 Adam: To find the monster we'll have to drain the loch some other way.
3 Jamie: I was thinking maybe we could try going out on a boat equipped with sonar or something.
4 Adam: Or we could dump in a billion tons of malted barley, distil it, and invite 7.5 billion Scots around for a taste!

Okay, okay, so there's no such thing as Scottish citizenship. You'd have to have the UK grant everyone in the world citizenship, and have Scotland grant them all residency. This simply requires that everyone in the world either:

invest £200,000 in creating a business and create two jobs in Scotland,

invest £2,000,000 in Scotland, or

find an employer in Scotland willing to sponsor them.

The obvious and easiest combination is that:

2.5 billion people each invest £200,000 and create two jobs in Scotland, and then